700 more flights canceled Monday after a chaotic travel weekend

Delta (DAL) alone canceled at least 214 flights Monday, or 7% of its operations, while United (UAL) canceled 122 flights and American Airlines (AAL) nixed 62. CNN has reached out to the three airlines for comment on the flight cancellations.

It’s going to be a summer of travel hell, experts warn. Though airlines received $54 billion in federal assistance during Covid’s peak to avoid involuntary layoffs, they now have fewer employees than before the pandemic — especially pilots — after offering buyouts and early retirement packages to trim staff and save money. As a result, operations can quickly fall apart when there’s bad weather, understaffed air traffic control centers or sick staff.

Atlanta’s Hartsfield-Jackson International Airport and the New York City area’s Newark Liberty International were most impacted by Monday’s cancellations, with Newark alone accounting for more than 100 canceled flights.

According to FlightAware, there were 634 US flight cancellations Saturday and 868 canceled Sunday.

“More than any time in our history, the various factors currently impacting our operation — weather and air traffic control, vendor staffing, increased Covid case rates contributing to higher-than-planned unscheduled absences in some work groups — are resulting in an operation that isn’t consistently up to the standards Delta has set for the industry in recent years,” said Delta Chief Customer Experience Officer Allison Ausband in an online post.

But critics say airlines should have anticipated these issues ahead of the summer travel season.

“When you stress-test the airline operation model, that’s when you see the same results,” Capt. Dennis Tajer, spokesperson for the Allied Pilots Association, the pilots union at American Airlines, said earlier this month.